Synchronizing Email Recipient Lists Using Block Partition Information

1. A computer-implemented method performed by a first device for replicating an email recipient list, the method comprising: receiving from a second device a first list of hashed blocks, each hashed block in the first list of hashed blocks being a compressed view of a block of records of a target email recipient list; receiving from the second device block partition information specifying partitioning of the target email recipient list into blocks of records from which the first list of hashed blocks was generated; after receiving the block partition information from the second device, generating by the first device a second list of hashed blocks from blocks of records of a local email recipient list based on the block partition information received from the second device so that the first device and the second device partition using the same technique and so that the first device does not require prior knowledge of the technique used by the second device; comparing the first list of hashed blocks to the second list of hashed blocks, each hashed block in the second list of hashed blocks being a compressed view of a block of records of the local email recipient list; identifying hashed blocks in the first list of hashed blocks that are different from their corresponding hashed blocks in the second list of hashed blocks; for each different hashed block, sending to the second device the corresponding block of records of the local email recipient list; and for at least one different hashed block, sending a request to repartition the block of records of the target email recipient list corresponding to the different hashed block, such that each sent block of records of the local email recipient list results in updating the corresponding block of records of the target email recipient list.

2. The method of claim 1 , wherein the compressed view is a hash value.

3. The method of claim 1 , wherein each block of records of the target email recipient list is a range of records in the target email recipient list.

4. The method of claim 3 , wherein each range of records is determined based on an alphabetized ordering of the records in the target email recipient list.

5. The method of claim 3 , wherein the range of records is ordered based on a predetermined random identifier associated with the records.

6. The method of claim 1 , wherein the block partition information for each hashed block specifies a beginning record, an ending record, and a number of records in the block of records corresponding to the hashed block.

7. The method of claim 1 further comprising: in response to sending the request to repartition the block of records of the target email recipient list corresponding to the different hashed block, receiving a list of hashed subblocks, each hashed subblock in the list of hashed subblocks being a compressed view of a subblock of the records of the target email recipient list corresponding to the different hashed block; and receiving block repartition information for each subblock in the list of hashed subblocks, wherein the block repartition information specifies the repartitioning of the records of the target email recipient list corresponding to the different hashed block for generating the list of hashed subblocks; using the received block repartition information to generate a local list of hashed subblocks, each hashed subblock in the local list of hashed subblocks being a compressed view of a subblock of the records of the local email recipient list corresponding to the different hashed block; identifying hashed subblocks in the local list of hashed subblocks that are different than their corresponding hashed subblocks in the received list of hashed subblocks.

8. The method of claim 7 further comprising, for each different hashed subblock, sending the corresponding subblock of records of the different block of records of the local email recipient list, such that the sent subblock of records of the different block of records of the local email recipient list updates the corresponding subblock of records of the different block of records of the target email recipient list.

9. A computer-implemented method performed by a first device for replicating an email recipient list, the method comprising: receiving from a second device a request to update the email recipient list, the request including block partition information specifying a partitioning technique for partitioning records of the email recipient list into blocks of records; and in response to receiving the request, partitioning the email recipient list into blocks of records based on the block partition information received from the second device so that the first device and the second device partition using the same technique and so that the first device does not require prior knowledge of the technique used by the second device; generating a compressed value for each of the blocks of records; sending a list of hashed blocks in response to the request, wherein the list of hashed blocks is a list of the compressed values for each of the blocks of records of the email recipient list such that the list of hashed blocks is used to identify blocks of records of the email recipient list that are different from corresponding blocks of records in a source email recipient list; and receiving a request to repartition a specified block of records of the email recipient list, the specified block having been identified as being different from the corresponding block of records in the source email recipient list.

10. The method of claim 9 , wherein a compressed value is a hash value of the block of records.

11. The method of claim 9 , wherein each block of records of the email recipient list is a range of records.

12. The method of claim 11 , wherein each range of records is determined based on an alphabetized ordering of the records in the email recipient list.

13. The method of claim 11 , wherein each range of records is ordered based on a predetermined random identifier associated with the records.

14. The method of claim 9 further comprising: in response to receiving the request to repartition the specified block of records, repartitioning the specified block of records into subblocks of records; generating a compressed value for each of the subblocks of records; and sending a list of hashed subblocks in response to the request to repartition the specified block of records, wherein the list of hashed subblocks is a list of the compressed values for each of the subblocks of records of the specified block of records of the email recipient list.

15. A non-transitory computer-readable storage media containing instructions for controlling a first device to replicate an email recipient list, by a method comprising: sending to a second device a request to update a target email recipient list; receiving from the second device a first list of hashed blocks, each hashed block in the first list of hashed blocks being a compressed view of a block of records of the target email recipient list; receiving from the second device block partition information specifying partitioning of the target email recipient list into blocks of records from which the first list of hashed blocks was generated; and after receiving the block partition information from the second device, generating by the first device a second list of hashed blocks from blocks of records of a local email recipient list based on the block partition information received from the second device so that the first device and the second device partition using the same technique and so that the first device does not require prior knowledge of the technique used by the second device comparing the first list of hashed blocks to the second list of hashed blocks, each hashed block in the second list of hashed blocks being a compressed view of a block of records of the local email recipient list; identifying hashed blocks in the first list of hashed blocks that are different from their corresponding hashed blocks in the second list of hashed blocks; for each different hashed block, sending to the second device the corresponding block of records of the local email recipient list for updating on the target email recipient list; and for at least one different hashed block, sending a request to repartition the block of records of the target email recipient list corresponding to the different hashed block.

16. The non-transitory computer-readable storage media of claim 15 , further comprising: for each different hashed block, determining whether to request repartitioning of the block of records of the target email recipient list corresponding to the different hashed block; upon determining to request repartitioning of the block of records of the target email recipient list corresponding to the different hashed block, sending the request to repartition the block of records of the target email recipient list corresponding to the different hashed block.

17. The non-transitory computer-readable storage media of claim 16 , further comprising: receiving a list of hashed subblocks, each hashed subblock in the received list of hashed subblocks being a compressed view of a subblock of the records of the target email recipient list corresponding to the different hashed block; comparing the received list of hashed subblocks to a local list of hashed subblocks, each hashed subblock in the local list of hashed subblocks being a compressed view of a subblock of the records of the local email recipient list corresponding to the different hashed block; identifying hashed subblocks in the local list of hashed subblocks that are different than their corresponding hashed subblocks in the received list of hashed subblocks; and for each different hashed subblock, sending the corresponding subblock of records of the local email recipient list for updating on the target email recipient list.